Recently, as performance of computers and various mobile electronic and communication devices gets higher, their sizes are being continuously miniaturized. However, the inner structure of the miniaturized mobile devices is very densely integrated, so that there is little empty space to thereby provide disadvantages in heat dissipation.
It is difficult for small-sized mobile devices such as notebook computers and sub-notebook computers of the electronic and communication devices to employ cooling devices to dissipate heat generated therefrom and discharge the heat to the exterior, due to their size. Conventional cooling devices may be a simple thermal conduction type device that a material having good thermal conductivity is installed appropriate to a package structure of the device. In addition, there exist a fan and heat pipe-type device, a liquid circulation-type device, and so on.
The fan and heat pipe-type device is provided with a vent hole formed at a side chassis of the device so that heat transported from a heat source through a heat pipe is discharged through the vent hole. The liquid circulation-type device, which is the most typical type device, has very excellent heat transport performance in comparison with other cooling type devices.
Such cooling type devices are being widely used in the compact mobile devices. However, as the electronic package structure in the compact mobile device becomes more and more densely integrated, there are difficulties in employing the conventional cooling devices due to its size.
That is, it is not easy to find a cooling method capable of transporting heat to a relatively long distance in the case that the package structure has a small inner volume and thickness. For example, when a small heat pipe is pressed to a thickness smaller than about 2 mm, its heat transport performance is remarkably reduced to make it difficult to transport the heat to a distance longer than about 50 mm. Meanwhile, other cooling methods also have disadvantages in thermal conductivity or size to make it difficult to apply them.